The Python No Spill Clean and Fill Aquarium Gravel Tube is a great way to keep your aquarium clean and fresh. The tube is made of high-quality PET plastic that is resistant to chemicals and does not break easily. The tube is easy to fill and refill, and it has a flat bottom that makes it easy to stand the tube on its side without tilting. The tube is also easy to bend and shape, so you can use it in any way that you want.